Author Topic: Strange rattle on de-acceleration  (Read 5568 times)

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AussieDave

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on: November 12, 2013, 06:29:03 am
Hi everyone. A couple of weeks ago I posted about I noise that I thought may have been a loose nut or something in the crank case. I looked behind both of the covers and did an oil change and ran it through a strainer but I didn't find anything. After the oil change the noise disappeared for a while untill I gave the bike a bit of a thrashing last week and now it's back. It is an intermittent rattle that happens with engine braking and sounds similar in tone to the noise made by the gear lever linkage . Like something is loose and kinda flicking about. Does anyone have a suggestion as to what could cause this? The motor itself is running fine.
"Glorious,stirring sight! The poetry of motion! The real way to travel! The only way to travel! ... O bliss ! O poop poop ! Oh my! Oh my!" - Toad of Toad Hall.


AVL Power!

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Reply #1 on: November 12, 2013, 08:38:06 am
I had the same rattle on my AVL, in my case it was the primary side chain. Did you check your primary side?



High On Octane

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Reply #2 on: November 12, 2013, 01:34:38 pm
More than likely 1 of 2 things.  Like dampking mentioned, it could be a loose primary chain adjustment or even a loose drive chain, but those tend to cause more of a "slapping" sound.  My guess is that your tappets are out of adjustment and beginning to develop too much play.  Normally when they are just starting to get loose they will act as you're describing, fairly quite upon acceleration but start chattering away the second you close the throttle.

Scottie
2001 Harley Davidson Road King


barenekd

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Reply #3 on: November 12, 2013, 05:47:35 pm
My guess would be the primary chain or clutch.
Bare
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Royalista

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Reply #4 on: November 12, 2013, 07:07:04 pm
You might also check your heatshield.
I went nearly berserk for over a month, searching for a similar sound, fearing the worst, as is common. Ultimately I found the slip that holds the front of the heatshield to the exhaust had broken off. That was the initial sound and after it fell off it was the front of the shield hitting the exhaust while revving and braking. Just a quick look.  :-\
moriunt omnes pauci vivunt


NorEaster

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Reply #5 on: November 12, 2013, 09:32:03 pm
You might also check your heatshield.
I went nearly berserk for over a month, searching for a similar sound, fearing the worst, as is common. Ultimately I found the slip that holds the front of the heatshield to the exhaust had broken off. That was the initial sound and after it fell off it was the front of the shield hitting the exhaust while revving and braking. Just a quick look.  :-\

I had the same problem. Tab on the pipe did not mate with the slot on the heat shield. (brand new bike)
Took off the shield and tried to make it all fit better; but it still rattled. Took a small bit of exhaust wrap and folded it up between the heat shield and the pipe and clamped the two together with a stainless hose clamp.
Put the clamp in the depressed area of the shield under where the kickstart lever is.
No more rattles for me.


Arizoni

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Reply #6 on: November 12, 2013, 11:28:25 pm
I doubt if it is the valve adjustment.  On the UCE bikes, there isn't any because the hydraulic valve lifters don't need it.

Has the rear chain been adjusted?  If it is too loose it can slap the rear swing arm.
Jim
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AussieDave

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Reply #7 on: November 13, 2013, 02:57:49 am
Thanks for the responses guys. I have been right over the chassis and checked/ tightened up pretty much everything. I have the hitchcocks pipe and shield,which is solid. I checked the primary chain and it was taut with the auto - tensioner functioning as it should. I put a new tyre on last week( thanks Wildbill) and adjusted my chain- so no mystery noise there either. It's got me - expletive deleted- . I guess the rocker covers should be my next option.
"Glorious,stirring sight! The poetry of motion! The real way to travel! The only way to travel! ... O bliss ! O poop poop ! Oh my! Oh my!" - Toad of Toad Hall.


Craig McClure

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Reply #8 on: November 13, 2013, 04:04:41 am
I have known muffler baffles to rattle, & make you crazy trying to find the noise.
Best Wishes, Craig McClure


High On Octane

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Reply #9 on: November 13, 2013, 05:01:48 am
I doubt if it is the valve adjustment.  On the UCE bikes, there isn't any because the hydraulic valve lifters don't need it.

I'll admit I've never wrenched on a UCE but to the best of my knowledge just about every valve train has some kind of valve adjustment regardless if it's hydraulic, flat tappet or roller.

Scottie
2001 Harley Davidson Road King


barenekd

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Reply #10 on: November 13, 2013, 09:26:51 pm
On Lycoming aircraft engines, the valve clearance is adjusted by different length pushrods. The range is something like .020-.080. This is how much the lifters need to pump up. But once they've pumped up there should be 0 clearance.
Bare
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Ducati Scotty

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Reply #11 on: November 13, 2013, 10:13:55 pm
I believe most auto hydraulic lifters are adjusted once when they are installed, and that's it.  Not sure if they do or need to do that on our bikes.

Scott


Craig McClure

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Reply #12 on: November 13, 2013, 11:53:21 pm
I do believe they are self adjusting pushrods. This was another selling point for me.
Best Wishes, Craig McClure


gashousegorilla

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Reply #13 on: November 14, 2013, 12:07:40 am
  No adjustment.  Like Bare describes above, it's spec'ed by rod length.  Which should put the rod down into the lifter, around the middle of the travel of the piston in the lifter.  When you go outside of stock spec's...... different valve train length or geometry, facing the head, gasket's, decking etc.  You may need different length, or adjustable rods.
« Last Edit: November 14, 2013, 03:41:07 pm by gashousegorilla »
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.


Arizoni

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Reply #14 on: November 14, 2013, 05:15:30 am
For what it's worth, the 500 UCE parts manual doesn't show any type of adjustment for the valve clearance.

It also does not show any other pushrods than the one intake length and one exhaust length.

Oddly, it does show two oversize cam bushings that are available in addition to the stock ones.  The use of these wouldn't have any effect on the camshaft to rocker arm distance though.
Jim
2011 G5 Deluxe
1999 Miata 10th Anniversary


High On Octane

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Reply #15 on: November 14, 2013, 01:11:33 pm
I guess that would explain why Dan Kearney's '12 Military runs soooo much quieter than mine.  :D 

Scottie
2001 Harley Davidson Road King


SSR

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Reply #16 on: November 25, 2013, 07:12:22 am
If there is play in cam spindle then it does makes a muted rattle. Get them checked along with the rockers bearings.


Blairio

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Reply #17 on: November 25, 2013, 07:26:51 am
Aussie Dave,  you mention you have  a hitchcocks pipe and shield, are you also running the Hitchcock's EFI bottle silencer? I run one of these, with a fishtail stuck on the end. The bolt-in baffle has a habit of working loose, and when it does it gives off a fiendish rattle on the over-run. Perhaps you could revert to the original exhaust system, which would rule out (or rule in) the silencer and baffle as a source of your noise?

Cheers,

Blairio


AussieDave

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Reply #18 on: November 25, 2013, 04:29:50 pm
Hey Blairo- my rattle turned out to be the chain- after I conviced myself several times that it wasn't ! What an idiot. It was rattling on de- celeration flicking the top of the case at it went in .i was lookin at the bottom section. It had stretched unevenly, so I've replaced it. Haven't been posting much coz I meet a girl- went to visit today in the country -cruised home on about125 k coz no- one was about -and lost my baffle .danm thing fell out . And I thought locktite was my friend! Yeah, mines a (loud) bottle.
 How does the fish- tail sound?
"Glorious,stirring sight! The poetry of motion! The real way to travel! The only way to travel! ... O bliss ! O poop poop ! Oh my! Oh my!" - Toad of Toad Hall.


Blairio

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Reply #19 on: November 25, 2013, 08:12:22 pm
AussiDave, the fishtail sounds great.  It takes the sharp edge off the exhaust note, which is useful for when I'm pulling away from my house early in the morning. Other than that it doesn't affect the way the engine runs, and certainly doesn't smother it.

The baffle on my EFI bottle silencer has come loose 3 times. Each time, the only thing that stopped it shooting clean out of the silencer was .. the fishtail. I finally got the baffle to stay put by using a longish bolt with two nuts tightened hard against each other (and loc-tite).  that seems to have done the trick!


Arizoni

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Reply #20 on: November 26, 2013, 12:05:16 am
IMO, loc-tite and almost every epoxy or superglue I can think of all go away when the temperature goes above 400*F.
A silencer gets well over that temperature on a long run so using one of the thread locking compounds is pretty much useless.

Mechanical methods of locking threads is about the only thing that will work in an exhaust system.  These include the jam nut method and there are special interference nuts used in the aircraft industry that will work if you can find them.  MS21043 is an example.
Jim
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1999 Miata 10th Anniversary


Ducati Scotty

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Reply #21 on: November 26, 2013, 12:07:07 am
They do make the self-locking nuts with metal instead of nylon locking.  A bit harder to find these days but they are out there.

Scott


AussieDave

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Reply #22 on: November 26, 2013, 02:47:54 am
Thanks for being such good blokes and offering your excellent suggestions:) I gotta say -my bike is much livelier without that plug in the pipe! I guess I am a motorcycle hoon at heart coz I love it! Damn it's loud though. I'm gonna see if I can get get a replacement from hitchcocks. In the meantime I will exercise discretion around those funny lookin cars with the blue lights . I think I'll get a fish tail while I'm at it -they do look cool!
"Glorious,stirring sight! The poetry of motion! The real way to travel! The only way to travel! ... O bliss ! O poop poop ! Oh my! Oh my!" - Toad of Toad Hall.


Blairio

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Reply #23 on: November 26, 2013, 08:37:36 am
AussieDave, here's my bike, with the EFI bottle silencer and Fishtail:



I have used the longer of the two Hitchcock heat shields to cover the join between header pipe and silencer, secured with a couple of stainless steel jubilee clips.

When I first unpacked the EFI bottle silencer I was surprised to see that there was only one mounting point for a bracket to fix the silencer to the frame, compared the original silencer's two mounting points. The mounting point on the frame just beside where the brake rod meets the rear brake foot pedal is unused. I queried Hitchcocks on this point, and they said that the bottle silencer was far lighter than the original, and a second mounting was not considered necessary. They offered to send me second bracket to double up on the first one, but so far I haven't felt the need for it.


AussieDave

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Reply #24 on: November 27, 2013, 12:10:41 am
Thanks Blario. ! Nice bike ...the fish looks wicked I reckon.what holds it on? The same bolt that retains the baffle?
"Glorious,stirring sight! The poetry of motion! The real way to travel! The only way to travel! ... O bliss ! O poop poop ! Oh my! Oh my!" - Toad of Toad Hall.


Blairio

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Reply #25 on: November 27, 2013, 04:40:23 am
Thanks, AussieDave.  I think Riviera Red looks great in the sunlight, although there's not much of that available in Scotland in Winter!

The fishtail is held on by a nut & bolt assembly which clamps the fishtail onto the exhaust pipe. It is facing the wheel, so you can't see it in the picture. The baffle bolt doesn't keep the fishtail on, but it does limit how far up the tailpipe you can slide the fishtail - if you see what I mean. In practice this isn't a problem. The fishtail has never worked loose, unlike the baffle.
« Last Edit: November 27, 2013, 04:45:56 am by Blairio »


AussieDave

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Reply #26 on: November 27, 2013, 03:35:59 pm
It does look good in the sunshine! Must be the low angle . You guys keep your sun n stars in the weirdest places. I love Scotland . Played a gig once in Ullapool lookin out at a loch like that . Felt just like playing in our local -Great people!
 
"Glorious,stirring sight! The poetry of motion! The real way to travel! The only way to travel! ... O bliss ! O poop poop ! Oh my! Oh my!" - Toad of Toad Hall.


mattsz

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Reply #27 on: November 27, 2013, 09:54:27 pm
I've played a gig in Ullapool, too!  Must be getting mighty dark right about this time of year...


AussieDave

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Reply #28 on: November 28, 2013, 12:06:12 am
I  am willing to bet the good people of Ullapool loved that there hurdy-gurdy Mattz!
 Maybe it's time ye played a visit down here!
  My (ahm) young lady friend was waxing lyrical ' bout a gurdy -ist playing in ballarat of all places , last week,apparently on a teaching grant for three years.
May have to investigate further.
"Glorious,stirring sight! The poetry of motion! The real way to travel! The only way to travel! ... O bliss ! O poop poop ! Oh my! Oh my!" - Toad of Toad Hall.